Converting coal in the ground directly into clean-burning gases could have huge environmental benefits--not the least of which would be the avoidance of destructive mining operations. The problem is, technology for underground coal gasification is still in its early stages.
Now the government of Alberta says it will give C$285 million ($271 million) to a coal gasification project by Calgary-based Swan Hills Synfuels that involves the deepest-ever operation to generate power from coal--without digging it up.
Previous demonstrations of the technology have turned coal seams as deep as 1,000 meters below the surface into clean-burning gas. In contrast, Swan Hills Synfuels' C$1.5 billion project proposes to reach down 1,400 meters. Working at that depth could lessen the threat of groundwater contamination from the smoldering decomposing coal. "We've got 800 meters of rock--a lot of it impermeable--between us and freshwater aquifers," says Swan Hills president Doug Shaigec.
What's more, if the technology can get at deeper layers of coal, it could allow access to much more of the fossil fuel, says Julio Friedmann, who is carbon management project leader for Lawrence Livermore National Laboratory in California.
When the project starts up in 2015, Swan Hills hopes to generate 300 megawatts of power from its coal gas while selling over 1.3 million tons of carbon dioxide per year. The CO2 could be used by oil producers and ultimately stored in oil wells. This could result in the storage of 10 to 20 million tons of carbon dioxide per year by 2020. That would help Alberta meet its 2020 goal for carbon capture of 25 to30 million tons per year, according to a report last month from an alliance of Canadian industrial firms.
The British are also looking to ramp up their carbon dioxide emissions, in their case looking to coal reserves under the North Sea - North Sea coal to be burnt underground.
Vast coal deposits lying deep beneath the North Sea will be burnt in situ to generate up to 5 per cent of Britain’s energy needs, under new plans approved by the Government last week.
The UK Coal Authority has awarded licences to Clean Coal, an Anglo-American company, to develop five offshore sites for a technology called Underground Coal Gasification (UGC).
The method, which has not been used on a commercial scale in the UK, although it is widely used in Australia [BG: this is a gross exaggeration], taps the high energy content of coal while doing away with the costly and labour-intensive need to mine it first.
Rohan Courtney, a former director of Tullow Oil who is chairman of Clean Coal, said that the potential for the technology was enormous. “There are enormous amounts of coal lying beneath the North Sea which have never been accessed,” he said. “This technology is going to open up the industry again in the UK.”
The sites approved for use stretch up to 10km offshore from Sunderland, Grimsby and Cromer on the shores of the North Sea, Canonbie, near Annan in Dumfries and Galloway on the other side of Scotland, and Swansea Bay, outside the entrance to the Bristol Channel. The combined coal reserves are estimated to be at least one billion tonnes, equivalent to more than one sixth of all the coal consumed in an average year around the world. Global consumption of coal is about 5.8 billion tonnes a year. Total consumption in the UK is about 80 million tonnes a year.